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Chapter 7: Q12 (page 312)

Formats of Confidence Intervals. In Exercises 9–12, express the confidence interval using the indicated format. (The confidence intervals are based on the proportions of red, orange, yellow, and blue M&Ms in Data Set 27 “M&M Weights” in Appendix B.)

Blue M&Ms Express the confidence interval 0.270±0.073 in the form ofp^-E<p<p^+E

Short Answer

Expert verified

The confidence interval is expressed as0.197<p<0.343.

Step by step solution

01

Given information

The confidence interval for the proportion of blue M&Ms is given as 0.270 ±0.073.

02

Expression of the confidence interval

The confidence interval for the population proportion can be expressed as follows:

p^-E<p<p^+E

The value written before the plus-minus sign is regarded as the sample proportion p^while the value written after the plus-minus sign is regarded as the margin of error (E).

Thus, the value ofp^-Eis computed below:

p^-E=0.27-0.073=0.197

The value of p^-Eis computed below:

p^+E=0.27+0.073=0.343

Therefore, the expression of the confidence interval of the proportion of blue M&Ms is equal to0.197<p<0.343.

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